[Qual] Uniformize code

htdocs/margin/admin/margin.php

htdocs/opensurvey/card.php

htdocs/opensurvey/results.php

htdocs/opensurvey/wizard/choix_autre.php

htdocs/opensurvey/wizard/choix_date.php

htdocs/opensurvey/wizard/create_survey.php

htdocs/paybox/admin/paybox.php

htdocs/paypal/admin/paypal.php

htdocs/product/admin/dynamic_prices.php

htdocs/product/admin/price_rules.php

htdocs/product/admin/product.php

htdocs/product/admin/product_tools.php

htdocs/product/composition/card.php

htdocs/product/dynamic_price/editor.php

htdocs/product/stock/card.php

htdocs/product/stock/massstockmove.php